Bicycle stem



FIG. 1 is a perspective view of a bicycle stem showing my new design;

FIG. 2 is a left side elevational view thereof;

FIG. 3 is a rear elevation view thereof;

FIG. 4 is a bottom plan view thereof;

FIG. 5 is a top plan view thereof; and

FIG. 6 is a front elevation view thereof. 

The ornamental design for a bicycle stem, as shown. 